Hydrodynamic measurement data set characterising the wake behind a single and various twin vertical axis turbines

The wake characteristics behind a single vertical axis turbine (VAT) and a range of twin turbine configurations, separated by two lateral spacings (Sy) and rotating in various rotational directions, were characterised using small-scale laboratory experiments at the Hydro-Environmental Research Centre at Cardiff University. Analysed configurations include: Approach flow Single VAT (SVAT) Twin VAT – same rotational direction, Sy=1.5D Twin VAT – same rotational direction, Sy=2D Twin VAT – counter rotating forward, Sy=1.5D Twin VAT – counter rotating forward, Sy=2D Twin VAT – counter rotating backward, Sy=1.5D Twin VAT – counter rotating backward, Sy=2D with D being the turbine diameter (D=0.12m). Hydrodynamics were measured using acoustic Doppler velocimetry for 9 cross-sections (y-z plane) in downstream direction (x/D=1,1.5,2,3,4,5,6,8,10D), comprising of 12-14 velocity profiles in lateral direction and 20 measurement points in vertical direction. Additional, upstream flow conditions were measured approximately 1m upstream of the turbine (x/D=-8.33) for six velocity profiles. The data set comprises of eight excel files, i.e., one per tested configurations, presenting first and second order hydrodynamic statistic for each measurement positions.